<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <script>
        // 对象执行方法时, 先查看自己是否有这个方法，没有则查看隐式原型
        // 就近原则

        function Star(name, age) {
            this.name = name;
            this.age = age;
            this.sing = function () {
                console.log('构造函数   唱歌');
            }
        }

        Star.prototype.sing = function () {
            console.log('显示原型   唱歌');
        }

        let eason = new Star('eason',22);

        eason.sing();

    </script>
</body>

</html>